Impeller



United States Patent O i IMPELLER George Albert Lyon, Detroit, Mich.

Application March 27, 1953, Serial N o. 345,193

2 Claims. (Cl. 17o-16,8)

The present invention relates to improvements in impellers and more especially concerns improvements in fluid impellers such as fans.

An important object of the presen-t invention is to provide an improved impeller construction having novel fluid impelling means.

Another object of the invention is to provide novel onepiece sheet metal impeller structure.

A further object of the invention is to provide a onepiece framed blade safety fan.

Still another object of the invention is to provide an irnproved method of making impellers.

Other objects, features and advantages of the present invention will be readily apparent from the following detailed description of a preferred embodiment thereof taken in conjunction with the accompanying drawings, in which:

Figure 1 is a face view of an impeller embodying features of the invention;

Figure 2 is a fragmentary transverse enlarged sectional view taken substantially on the line II-II of Figure l;

Figure 3 is an enlarged fragmentary, substantially segmental face view of a blank from which an impeller ac-V cording to the present invention is made and showing the blank as it appears at an intermediate stage in the making of an impeller; and

Figure 4 is a fragmentary transverse sectional view taken substantially on the line IV--IV of Figure 3.

As best seen in Figures l and 2 an impeller is provided which embodies a peripheral safety frame about the fluid motivating blades thereof. To this end the impeller comprises a central hub portion 5 which in the present instance s shown as flat with an annular solid peripheral frame ring or ange 7 of larger diameter with an intermediate impeller blade or vane section 8. The impeller is constructed from a single piece of sheet metal of appropriate grade and gauge, depending upon the size and service requirements of the unit. In a desirable construction stainless steel sheet may be used, although brass or other self-sustaining sheet metal may be utilized.

The central hub portion 5 of the impeller may be of as large or small diameter as desired, and where, in the illustrative embodiment as shown in Fig. 1, the impeller is of a type adapted for use as an automobile fan, it may be provided with a central aperture 9 for projection therethrough of an automobile crankshaft terminal. Alternatively, or in addition thereto, the central hub or attachment ange 5 may be provided with a series of bolt holes 10 disposed in uniform spaced relation about the center of the central attachment flange, and in the present instance about the central aperture 9.

Certain advantages such as rigidity in minimum diameter, tunneling of impelled or suction uid, and the like, accrue from having the impeller of generally cupshape as accomplished by angular disposition of the annular outer marginal framing ange 7. As shown herein, the flange 7 may be of generally frusto-conical outwardly flaring shape, and reinforced at its outer margin by an annular generally return bent head 11. So as to avoid 2,779,424 Patented Jan. 29, 1957 ICC fluid turbulence at the inside of the impeller cup, the bead 11 is preferably turned outwardly.

According to the present invention, the intermediate annular portion 8 of the impeller is provided with a series of impeller blades or vanes 12 which are connected integrally in one piece at their inner ends to the central attachment flange 5, While at their outer ends they are integrally connected in one piece with the framing llange 7. In the illustrative embodiment of the invention, the impeller vanes 12 are constructed and arranged for impelling lluid from the inside of the impeller cup toward the axially outer side of the impeller as indicated bythe directional arrow in Fig. 2, upon rotation of the impeller counterclockwise as viewed in Fig. l. To this end, the impeller blades 12 are angled obliquely, uniformly and are bowed on respective transverse axes to afford etlicient lluid scoops for impelling fluid in the rotation of the impeller. In the attainment of the bowed, scoop formation of the vanes 12, they are also of a longitudinaly sinuous form, with the outer end portions of the vanes offset circumferentially from the inner end portions of the vanes.

In the efficient and economical formation of the vanes 12 of the impeller, without the use of any forming dies, but entirely by a metal stressing and setting operation, I utilize a process that I have developed. According to my method, the impeller is initially spun or stamped into a shape substantially as depicted in Figs. 3 and 4 wherein the central attachment flange 5, and the Outer marginal framing ange 7 are completed as to relative shape and relative radial disposition, while the intermediate portion 8 of the cover is shaped into uniform radially ogee contour. The ogee contour is selected for the particular operating characteristics or final shape desired in the nished vanes 12.

At uniformly spaced intervals, the intermediate portion 8 of the cover is provided with radially extending slots 13, thereby separating the intermediate portion 8 into the desired number of respective vane sections V. By the radial disposition of the slots 13, the vane sections V are of tapering width from their inner ends towards their outer ends, that is of gradually increasing width.

Where, as in the present instance, the maximum fluid scooping or impelling action of the vanes is desired in the portions of the vanes nearer the framing margin 7 than near the center of the impeller, as is desirable in an automobile fan, not only is the curvature of the radially outer portions of the vane sections V of larger concave radius than the convex radius of the radially inner portions of the vane sections, but the slots 13 are formed of substantially T-shape at their radially outer ends so as to afford circumferentially oppositely directed branch cutouts or recesses or notches 14 by which the connection to the framing ilange 7 is reduced to a relatively narrow central neck 15. By preference, the outer end corners of the vane sections V are rounded ott' on a radius as indicated at 17. The partially completed impeller blank now appears as shown in full outline in Figs. 3 and 4 and in dash outline in Fig. 2 insofar as the intermediate portion 8 of the impeller is concerned.

Completion of the impeller formation is effected by relatively angularly turning the attachment flange portion 5 and Vthe framing flange portion 7 of the blank, thereby causing uniform deliection or distortion of the vane sections V and a permanent setting twisting and tilting of the vane sections to provide the vanes 12. In order to afford vanes tilted in the direction indicated in Figs. 1 and 2, relative counterclockwise movement of the inner ange portion 5 as against a relative clockwise movement of the outer flange member 7 may be accomplished as schematically indicated by the directional arrows in Fig. 3 so that the inner and outer portions 5 and 7 are angularly offset as indicated by the offsetting of the schematic reference lines A and B. It will be understood, of course,

'that as al practical matter one of the portions 5 and 7 may be held stationary while the other ofsaid portions 1s fangularly relatively turned, or both of such portions may be simultaneously turned anf'ulariy in relatively opposite direction. Thev extent of the relative angular turning of 'the portions 5 and 7 will. determine the pitch-of the vanes l2. Furthermore, the direction of relative angular turnof the portions and will determine the direction of tilt orpitch of thevanes 12. For example, if the vanes 12 are to be tilted or pitched oppositely to the position thereof shown in Figs. l and 2 or as indicated dash outline in Fig. 3, then relative turning of the portions 5 and 7 should be reversed from that indicated by the arrows at A and B in Fig. 3. The sheet metal atI the end' portions of the vanev sectionstaltes a permanent sety in the pitched condition of the vanes. All of thezvanes are of'uniforrn contour and pitch, if the vane sectionsV are initially of uniformshape.

Additional variations in the specific shape of thelvanes 12 may be effected by having. the-radial slots 13` formed spirally or angled fromV theV radial; The width and; the

spacing ofthe slots 13 are other. variable'factors` affordingy choice as to the shape or pitch characteristics-of the ultimate vanes. Variations, as to fluid' impelling action of the vanesk 12 in their radial extent' may be precalculated by appropriately modifying theY original sinuosityA of the intermediate sectionz of the impeller;

The sinuous formation of the intermediate. section 8 affords adequatematerial for stretching of the vanesections V as an incident toy the angular-*deflection of the vanes, without distorting the inner attachment flangezportion 5. or the outer framing flange portion 7 ofthe impeller.

As best visualized in Figs. 2 and 4, the inner terminal junctures of the vanes 12 with the flange 5 occurs at a juncture rib 1d; At their outer ends the vanes l2 at the juncture necks 15 are also of preferably rib-like form.

The finished impeller affords a strong shape-sustaining structure in which the radially inner and radially outer portions are resiliently connected by the vanes 12. The outer marginal framing flange 'l with its finishing bead 11 affords a safety frame about the ends of the impeller vanes or blades 12.

It will be understood that modifications and variations may be effected without departing from the scope ofthe novel concepts of the present invention.

I claimas my invention:

1.In an impeller construction, a one piece sheet metal body including a central circular attachment flange portion and aradially outer generally frusto-conical marginal flange portion, with a uniform'series of laterally separated air impelling vanes integrally connected in one piece at radially inner endsl thereof to said centralfilange portion and at radially outer ends thereof to said marginalflange, saidy vanes being` of both longitudinal and transverse sinuousformation and with the radially outer portions thereof rection toward which said marginal flange projects and" obliquely tilted relative to the plane of said inner circular attachment flange whereby to enable scooping of air axially outwardly from the substantially funnel structure provided by said outer marginal flange to funnel air toward said vanes, the ends of said vanes adjacent to said outer marginal flange beingy connected thereto by juncture neck connections which. are substantially narrower than the adjacent Width of the vanes and are short andv angular whereby to effect connection with the marginal flange in minimum space to have the adjacent scoop ends of the vanes cl'oseV tothe adjacentv edge ofthel marginal flange, said connection nfrzcltsrbeingl substantially rigid and parallel to the adjacent edge of the marginal flange.

2. in an impeller construction, a one-piece sheet metal body includin5F a central circular attachment flange portion and a radially outer generally frusto-conical marginal flange portion, with aV uniform series of laterally separated air impelling vanes integrally connectedy in one piece at radially inner ends thereof to said central flange portion and at radially outer ends thereof tosaid marginal flange, said vanes being of both longitudinal-and transverse sinuous formation and with the radially outer portions there` of of substantially greater width and bowed in the axial direction toward which said marginalv llange'projects and obliquely tilted relative to the plane of said inner circular attachment flange whereby Ito enable scooping of air axially outwardly from the substantially funnel structure provided by said outer marginaly flange to funnel air toward said vanes, the ends of said vanes adjacent to said outer marginal flange being connected thereto by juncture neck connections which are substantially narrower than the adjacent width of the vanes and are short and angular whereby to effect connection with the marginal flange in minimum space to-have the adjacentscoop ends of' t'he vanes close to the adjacent edge of the marginal flange, said connection necks being substantiallyy rigid and parallel to the adjacent edge of the marginal flange, said vanes beingy connected throughout their inner end width tosaid inner circular attachment flange.

References Cited in the file of this patent UNITED STATES PATENTS 693,328 Morgan Feb. 1,1, 1902 1,023,272 Oakes Apr. 16, 1912 1,029,907 Arnold June 18, 1912 1,135,451 Heath Apr. 13, 1915 1,377,300 Withington May 10,` 1921 1,620,875 Currie Mar. 15, 1927- 1,684,601 Shpater' Sept. 18, 1.9.28 1,872,483 Meyer Aug. 1'6, 1932 1,895,252 Kontos Jan. 24, 1933: 2,186,837 Meli/.fallan lan, 9 1,940. 2,336,3034 Schubert Dec; 7 1943 2,542,251. Hueglin Feb, 20, 195,1 

